The 5'-triphosphates of 1-(2'-deoxy-2'-fluoro-beta-D-arabinofuranosyl)-5-methyluracil, 1-(2'-deoxy-2'-fluoro-beta-D-arabinofuranosyl)-5-iodocytosine, 1-(2'-deoxy-2'-fluoro-beta-D-arabinofuranosyl)-5-methylcytosine, 9-[(2-hydroxyethoxy)methyl]guanine, and 9-(1,3-dihydroxy-2-propoxymethyl)guanine had lower Ki values for Epstein-Barr virus DNA polymerase than has been reported elsewhere for host DNA polymerase. Inhibition of DNA elongation by these analogs ranged from moderate to strong, suggesting that preferential incorporation of these analogs into DNA by virus DNA polymerase may contribute to antiviral selectivity.